[参考译文] LAUNCHXL-F28379D：使用多个 PWM 模块时出现 PWM 干扰

admin

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https://e2e.ti.com/support/microcontrollers/c2000-microcontrollers-group/c2000/f/c2000-microcontrollers-forum/1123147/launchxl-f28379d-pwm-glitches-when-using-multiple-pwm-modules

器件型号：LAUNCHXL-F28379D

大家好、

我使用 EPWM4A、EPWM5A 和 EPWM6A 在各种频率和占空比下生成独立的 PWM 信号。出于某种原因、当我修改一个模块的 PWM 占空比时、其他模块会闪烁和抖动。例如、如果我更改 EPWM4A 的占空比、我会注意到 EPWM6A 上的小毛刺脉冲。同样、在调整 EPWM6A 的占空比时、我注意到 EPWM4A 上出现毛刺和闪烁。

是否有任何关于这种情况发生的想法？我需要 PWM 保持稳定！我尝试使用不同的同步源进行实验、但我没有找到任何解决方案。

我希望有人能帮我。

谢谢、

Matthew

3 年多前

0 admin 3 年多前

TI__Guru**** 2048860 points

请注意，本文内容源自机器翻译，可能存在语法或其它翻译错误，仅供参考。如需获取准确内容，请参阅链接中的英语原文或自行翻译。

您好、Matthew、

您是否链接了不同 ePWM 模块的比较值？您能否分享您的 EPWM4A、5A 和6A 初始化信息？

此致、

Marlyn

0 admin 3 年多前

TI__Guru**** 2048860 points

请注意，本文内容源自机器翻译，可能存在语法或其它翻译错误，仅供参考。如需获取准确内容，请参阅链接中的英语原文或自行翻译。

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void EPWM_init(){
    EPWM_setClockPrescaler(myEPWM4_BASE, EPWM_CLOCK_DIVIDER_1, EPWM_HSCLOCK_DIVIDER_2);
    EPWM_setTimeBasePeriod(myEPWM4_BASE, 0);
    EPWM_setTimeBaseCounter(myEPWM4_BASE, 0);
    EPWM_setTimeBaseCounterMode(myEPWM4_BASE, EPWM_COUNTER_MODE_STOP_FREEZE);
    EPWM_disablePhaseShiftLoad(myEPWM4_BASE);
    EPWM_setPhaseShift(myEPWM4_BASE, 0);
    EPWM_setCounterCompareValue(myEPWM4_BASE, EPWM_COUNTER_COMPARE_A, 0);
    EPWM_setCounterCompareShadowLoadMode(myEPWM4_BASE, EPWM_COUNTER_COMPARE_A, EPWM_COMP_LOAD_ON_CNTR_ZERO);
    EPWM_setCounterCompareValue(myEPWM4_BASE, EPWM_COUNTER_COMPARE_B, 0);
    EPWM_setCounterCompareShadowLoadMode(myEPWM4_BASE, EPWM_COUNTER_COMPARE_B, EPWM_COMP_LOAD_ON_CNTR_ZERO);
    EPWM_setActionQualifierAction(myEPWM4_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_ZERO);
    EPWM_setActionQualifierAction(myEPWM4_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_PERIOD);
    EPWM_setActionQualifierAction(myEPWM4_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_UP_CMPA);
    EPWM_setActionQualifierAction(myEPWM4_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_DOWN_CMPA);
    EPWM_setActionQualifierAction(myEPWM4_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_UP_CMPB);
    EPWM_setActionQualifierAction(myEPWM4_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_DOWN_CMPB);
    EPWM_setActionQualifierAction(myEPWM4_BASE, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_ZERO);
    EPWM_setActionQualifierAction(myEPWM4_BASE, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_PERIOD);
    EPWM_setActionQualifierAction(myEPWM4_BASE, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_UP_CMPA);
    EPWM_setActionQualifierAction(myEPWM4_BASE, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_DOWN_CMPA);
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void EPWM_init(){
    EPWM_setClockPrescaler(myEPWM4_BASE, EPWM_CLOCK_DIVIDER_1, EPWM_HSCLOCK_DIVIDER_2);
    EPWM_setTimeBasePeriod(myEPWM4_BASE, 0);
    EPWM_setTimeBaseCounter(myEPWM4_BASE, 0);
    EPWM_setTimeBaseCounterMode(myEPWM4_BASE, EPWM_COUNTER_MODE_STOP_FREEZE);
    EPWM_disablePhaseShiftLoad(myEPWM4_BASE);
    EPWM_setPhaseShift(myEPWM4_BASE, 0);
    EPWM_setCounterCompareValue(myEPWM4_BASE, EPWM_COUNTER_COMPARE_A, 0);
    EPWM_setCounterCompareShadowLoadMode(myEPWM4_BASE, EPWM_COUNTER_COMPARE_A, EPWM_COMP_LOAD_ON_CNTR_ZERO);
    EPWM_setCounterCompareValue(myEPWM4_BASE, EPWM_COUNTER_COMPARE_B, 0);
    EPWM_setCounterCompareShadowLoadMode(myEPWM4_BASE, EPWM_COUNTER_COMPARE_B, EPWM_COMP_LOAD_ON_CNTR_ZERO);
    EPWM_setActionQualifierAction(myEPWM4_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_ZERO);
    EPWM_setActionQualifierAction(myEPWM4_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_PERIOD);
    EPWM_setActionQualifierAction(myEPWM4_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_UP_CMPA);
    EPWM_setActionQualifierAction(myEPWM4_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_DOWN_CMPA);
    EPWM_setActionQualifierAction(myEPWM4_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_UP_CMPB);
    EPWM_setActionQualifierAction(myEPWM4_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_DOWN_CMPB);
    EPWM_setActionQualifierAction(myEPWM4_BASE, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_ZERO);
    EPWM_setActionQualifierAction(myEPWM4_BASE, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_PERIOD);
    EPWM_setActionQualifierAction(myEPWM4_BASE, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_UP_CMPA);
    EPWM_setActionQualifierAction(myEPWM4_BASE, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_DOWN_CMPA);
    EPWM_setActionQualifierAction(myEPWM4_BASE, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_UP_CMPB);
    EPWM_setActionQualifierAction(myEPWM4_BASE, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_DOWN_CMPB);

    EPWM_setClockPrescaler(myEPWM5_BASE, EPWM_CLOCK_DIVIDER_1, EPWM_HSCLOCK_DIVIDER_2);
    EPWM_setTimeBasePeriod(myEPWM5_BASE, 0);
    EPWM_setTimeBaseCounter(myEPWM5_BASE, 0);
    EPWM_setTimeBaseCounterMode(myEPWM5_BASE, EPWM_COUNTER_MODE_STOP_FREEZE);
    EPWM_disablePhaseShiftLoad(myEPWM5_BASE);
    EPWM_setPhaseShift(myEPWM5_BASE, 0);
    EPWM_setCounterCompareValue(myEPWM5_BASE, EPWM_COUNTER_COMPARE_A, 0);
    EPWM_setCounterCompareShadowLoadMode(myEPWM5_BASE, EPWM_COUNTER_COMPARE_A, EPWM_COMP_LOAD_ON_CNTR_ZERO);
    EPWM_setCounterCompareValue(myEPWM5_BASE, EPWM_COUNTER_COMPARE_B, 0);
    EPWM_setCounterCompareShadowLoadMode(myEPWM5_BASE, EPWM_COUNTER_COMPARE_B, EPWM_COMP_LOAD_ON_CNTR_ZERO);
    EPWM_setActionQualifierAction(myEPWM5_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_ZERO);
    EPWM_setActionQualifierAction(myEPWM5_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_PERIOD);
    EPWM_setActionQualifierAction(myEPWM5_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_UP_CMPA);
    EPWM_setActionQualifierAction(myEPWM5_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_DOWN_CMPA);
    EPWM_setActionQualifierAction(myEPWM5_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_UP_CMPB);
    EPWM_setActionQualifierAction(myEPWM5_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_DOWN_CMPB);
    EPWM_setActionQualifierAction(myEPWM5_BASE, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_ZERO);
    EPWM_setActionQualifierAction(myEPWM5_BASE, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_PERIOD);
    EPWM_setActionQualifierAction(myEPWM5_BASE, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_UP_CMPA);
    EPWM_setActionQualifierAction(myEPWM5_BASE, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_DOWN_CMPA);
    EPWM_setActionQualifierAction(myEPWM5_BASE, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_UP_CMPB);
    EPWM_setActionQualifierAction(myEPWM5_BASE, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_DOWN_CMPB);

    EPWM_setClockPrescaler(myEPWM6_BASE, EPWM_CLOCK_DIVIDER_1, EPWM_HSCLOCK_DIVIDER_2);
    EPWM_setTimeBasePeriod(myEPWM6_BASE, 0);
    EPWM_setTimeBaseCounter(myEPWM6_BASE, 0);
    EPWM_setTimeBaseCounterMode(myEPWM6_BASE, EPWM_COUNTER_MODE_STOP_FREEZE);
    EPWM_disablePhaseShiftLoad(myEPWM6_BASE);
    EPWM_setPhaseShift(myEPWM6_BASE, 0);
    EPWM_setCounterCompareValue(myEPWM6_BASE, EPWM_COUNTER_COMPARE_A, 0);
    EPWM_setCounterCompareShadowLoadMode(myEPWM6_BASE, EPWM_COUNTER_COMPARE_A, EPWM_COMP_LOAD_ON_CNTR_ZERO);
    EPWM_setCounterCompareValue(myEPWM6_BASE, EPWM_COUNTER_COMPARE_B, 0);
    EPWM_setCounterCompareShadowLoadMode(myEPWM6_BASE, EPWM_COUNTER_COMPARE_B, EPWM_COMP_LOAD_ON_CNTR_ZERO);
    EPWM_setActionQualifierAction(myEPWM6_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_ZERO);
    EPWM_setActionQualifierAction(myEPWM6_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_PERIOD);
    EPWM_setActionQualifierAction(myEPWM6_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_UP_CMPA);
    EPWM_setActionQualifierAction(myEPWM6_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_DOWN_CMPA);
    EPWM_setActionQualifierAction(myEPWM6_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_UP_CMPB);
    EPWM_setActionQualifierAction(myEPWM6_BASE, EPWM_AQ_OUTPUT_A, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_DOWN_CMPB);
    EPWM_setActionQualifierAction(myEPWM6_BASE, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_ZERO);
    EPWM_setActionQualifierAction(myEPWM6_BASE, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_PERIOD);
    EPWM_setActionQualifierAction(myEPWM6_BASE, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_UP_CMPA);
    EPWM_setActionQualifierAction(myEPWM6_BASE, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_DOWN_CMPA);
    EPWM_setActionQualifierAction(myEPWM6_BASE, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_UP_CMPB);
    EPWM_setActionQualifierAction(myEPWM6_BASE, EPWM_AQ_OUTPUT_B, EPWM_AQ_OUTPUT_NO_CHANGE, EPWM_AQ_OUTPUT_ON_TIMEBASE_DOWN_CMPB);
}

0 admin 3 年多前

TI__Guru**** 2048860 points

请注意，本文内容源自机器翻译，可能存在语法或其它翻译错误，仅供参考。如需获取准确内容，请参阅链接中的英语原文或自行翻译。

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void SYNC_init(){
    SysCtl_setSyncOutputConfig(SYSCTL_SYNC_OUT_SRC_EPWM1SYNCOUT);
    // For EPWM1, the sync input is: SYSCTL_SYNC_IN_SRC_EXTSYNCIN1
    SysCtl_setSyncInputConfig(SYSCTL_SYNC_IN_EPWM4, SYSCTL_SYNC_IN_SRC_EPWM1SYNCOUT);
    SysCtl_setSyncInputConfig(SYSCTL_SYNC_IN_EPWM7, SYSCTL_SYNC_IN_SRC_EPWM1SYNCOUT);
    SysCtl_setSyncInputConfig(SYSCTL_SYNC_IN_EPWM10, SYSCTL_SYNC_IN_SRC_EPWM1SYNCOUT);
    SysCtl_setSyncInputConfig(SYSCTL_SYNC_IN_ECAP1, SYSCTL_SYNC_IN_SRC_EPWM1SYNCOUT);
    SysCtl_setSyncInputConfig(SYSCTL_SYNC_IN_ECAP4, SYSCTL_SYNC_IN_SRC_EPWM1SYNCOUT);
    // SOCA
    SysCtl_enableExtADCSOCSource(0);
    // SOCB
    SysCtl_enableExtADCSOCSource(0);
}
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void SYNC_init(){
	SysCtl_setSyncOutputConfig(SYSCTL_SYNC_OUT_SRC_EPWM1SYNCOUT);
	// For EPWM1, the sync input is: SYSCTL_SYNC_IN_SRC_EXTSYNCIN1
	SysCtl_setSyncInputConfig(SYSCTL_SYNC_IN_EPWM4, SYSCTL_SYNC_IN_SRC_EPWM1SYNCOUT);
	SysCtl_setSyncInputConfig(SYSCTL_SYNC_IN_EPWM7, SYSCTL_SYNC_IN_SRC_EPWM1SYNCOUT);
	SysCtl_setSyncInputConfig(SYSCTL_SYNC_IN_EPWM10, SYSCTL_SYNC_IN_SRC_EPWM1SYNCOUT);
	SysCtl_setSyncInputConfig(SYSCTL_SYNC_IN_ECAP1, SYSCTL_SYNC_IN_SRC_EPWM1SYNCOUT);
	SysCtl_setSyncInputConfig(SYSCTL_SYNC_IN_ECAP4, SYSCTL_SYNC_IN_SRC_EPWM1SYNCOUT);
	// SOCA
	SysCtl_enableExtADCSOCSource(0);
	// SOCB
	SysCtl_enableExtADCSOCSource(0);
}

0 admin 3 年多前

TI__Guru**** 2048860 points

请注意，本文内容源自机器翻译，可能存在语法或其它翻译错误，仅供参考。如需获取准确内容，请参阅链接中的英语原文或自行翻译。

这里是我如何调节占空比。

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// Set PWM (EPWM4A) duty cycle
// Arguments: the desired duty cycle as a decimal (0-1)
// Outputs: none, but the PWM output will be affected.
void apply_PWM4A(float duty){
    pwm4Signal.dutyValA = duty;
    //
    // Disable sync(Freeze clock to PWM as well)
    //
    SysCtl_disablePeripheral(SYSCTL_PERIPH_CLK_TBCLKSYNC);
    //
    // Configuring ePWM module for desired frequency and duty
    //
    EPWM_configureSignal(myEPWM4_BASE, &pwm4Signal);
//    EPWM_configureSignal(myEPWM2_BASE, &pwmSignal);
//    EPWM_configureSignal(myEPWM3_BASE, &pwmSignal);
    //
    // ePWM4 SYNCO is generated on CTR=0
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// Set PWM (EPWM4A) duty cycle
// Arguments: the desired duty cycle as a decimal (0-1)
// Outputs: none, but the PWM output will be affected.
void apply_PWM4A(float duty){

    pwm4Signal.dutyValA = duty;

    //
    // Disable sync(Freeze clock to PWM as well)
    //
    SysCtl_disablePeripheral(SYSCTL_PERIPH_CLK_TBCLKSYNC);

    //
    // Configuring ePWM module for desired frequency and duty
    //
    EPWM_configureSignal(myEPWM4_BASE, &pwm4Signal);
//    EPWM_configureSignal(myEPWM2_BASE, &pwmSignal);
//    EPWM_configureSignal(myEPWM3_BASE, &pwmSignal);

    //
    // ePWM4 SYNCO is generated on CTR=0
    //
    EPWM_setSyncOutPulseMode(myEPWM4_BASE, EPWM_SYNC_OUT_PULSE_ON_COUNTER_ZERO);

    //
    // Enable sync and clock to PWM
    //
    SysCtl_enablePeripheral(SYSCTL_PERIPH_CLK_TBCLKSYNC);
}

0 admin 3 年多前

TI__Guru**** 2048860 points

请注意，本文内容源自机器翻译，可能存在语法或其它翻译错误，仅供参考。如需获取准确内容，请参阅链接中的英语原文或自行翻译。

您好、Matthew、

感谢您共享配置。在您的应用中、您在哪里调用"Apply_PWM4A"函数？一般来说、我不建议禁用 TBCLKSYNC、调用 configureSignal 函数、然后重新启用 TBCLKSYNC。您所做的是冻结时基计数器的中间操作、然后根据通过 configureSignal 传递的值重置 EPWM、该值的变化不仅仅是占空比。由于您已经启用了影子加载、我建议您仅更新'Apply_PWM4A'函数中的比较值、如下所示：

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    EPWM_setCounterCompareValue(myEPWM4_BASE, EPWM_COUNTER_COMPARE_A, 50);
    EPWM_setCounterCompareValue(myEPWM4_BASE, EPWM_COUNTER_COMPARE_B, 100);
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    EPWM_setCounterCompareValue(myEPWM4_BASE, EPWM_COUNTER_COMPARE_A, 50);
    EPWM_setCounterCompareValue(myEPWM4_BASE, EPWM_COUNTER_COMPARE_B, 100);

新的比较值将在下一次时基计数器等于零时生效。

在初始化期间、还可以调用以下代码行：

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    EPWM_setSyncOutPulseMode(myEPWM4_BASE, EPWM_SYNC_OUT_PULSE_ON_COUNTER_ZERO);
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    EPWM_setSyncOutPulseMode(myEPWM4_BASE, EPWM_SYNC_OUT_PULSE_ON_COUNTER_ZERO);

此致、

Marlyn

0 admin 3 年多前

TI__Guru**** 2048860 points

请注意，本文内容源自机器翻译，可能存在语法或其它翻译错误，仅供参考。如需获取准确内容，请参阅链接中的英语原文或自行翻译。

感谢您的回复。这是有道理的、但我应该如何根据所需的占空比计算比较值？

Matthew

0 admin 3 年多前

TI__Guru**** 2048860 points

请注意，本文内容源自机器翻译，可能存在语法或其它翻译错误，仅供参考。如需获取准确内容，请参阅链接中的英语原文或自行翻译。

您好、Matthew、

[~ userid="524634" URL"/support/microcontrollers/C2000-microcontrollers-group/C2000/f/C2000-microcontrollers-forum/112347/launchxl-f28379d-PWM-glitchs-when 使用多个 PWM-modules/4166280#4166280"]如何根据所需占空比计算比较值[报价]

以下视频(https://training.ti.com/c2000-enhanced-pulse-width-modulator-epwm-time-base-submodule)和本应用报告(C2000 ePWM 开发人员指南)对此进行了说明

此致、

Marlyn

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[参考译文] LAUNCHXL-F28379D：使用多个 PWM 模块时出现 PWM 干扰